The human body cannot synthesize certain amino acids that are necessary for health and growth, and instead must obtain them from food and beverage. These amino acids are called the “essential amino acids”, and include Histidine, Isoleucine, Leucine (Leu), Lysine, Methionine, Phenylalanine, Threonine, Tryptophan, and Valine.
Traditionally, desirable mixtures of amino acids, such as mixtures comprising the essential amino acids, have been provided by hydrolyzing a protein with relatively high levels of essential amino acids, such as whey protein, or by combining free amino acids in a mixture that, optionally, may also include a hydrolyzed protein such as whey. However, the taste of such mixtures is very difficult to predict or to control; and they may be deemed unsuitable or undesirable for certain uses. As a result, flavoring agents sometimes have to be included into such mixtures to mask the taste of the free amino acids and/or hydrolyzed protein.
In some cases, compositions where a proportion of the amino acid content is provided by polypeptides or proteins are found to taste better than compositions where a higher proportion of total amino acids is provided as free amino acids or as certain hydrolyzed proteins. The availability of such polypeptide based or protein based compositions has been limited, however, because nutritional formulations have traditionally been made from protein which is isolated from natural food products, such as whey isolated from milk or soy protein isolated from soy. The amino acid profiles of those proteins do not necessarily meet the amino acid requirements for a mammal.
Advantageously, the present invention provides a class of novel peptides comprising a Leu-Leu moiety and their use in food and beverage such as coffee. The present invention exhibits numerous merits over the prior art. For example, the peptides provide at least some essential amino acids (e.g. Leucine); and the peptides improve the taste profile of foods and beverages, such as for example coffee, when added therein.